Faslodex

Class: ERD (estrogen receptor downregulator) hormonal therapy. There are no other ERDs used to treat breast cancer.

How it works: ERDs block the effects of estrogen in breast tissue by attaching to the estrogen receptors in breast cells, by reducing the number of estrogen receptors, and by changing the shape of the estrogen receptors so they don't work as well.

Uses: Faslodex is used alone as the first treatment for postmenopausal women diagnosed with hormone-receptor-positive, HER2-negative, advanced-stage breast cancer that hasn’t been treated with hormonal therapy. Faslodex also is used to treat postmenopausal women diagnosed with metastatic, hormone-receptor-positive breast cancer that has stopped responding to other hormonal therapy medicines, such as tamoxifen.

How it's given: Faslodex is a liquid that is given once a month as an injection into a muscle, usually at your doctor's office.